Early Rounds: Activate Warrior (3) Synergy effect with God of War and other 2-star Warrior pieces. Note that the other chosen Warriors can't activate any Race effects. Or you can activate Mech (2) Synergy effect with Heaven Bomber, Sky Breaker or Ripper. Devine Mage strategy ¡s highly dependent on the Gold brought by winning streaks, that is, you need to get 40 or 50 Gold in the early rounds.
Mid-rounds:With 50 Gold at hand, you can Buy Exp with the Interest to reach Lv.8. During this period, try to get The Source and other Mage pieces with AOE Damage. You can replace the unnecessary pieces with the main ones once they reach 2 stars. Note that don't activate any Race Synergy effect while replacing.
Later Rounds: Upon reaching Lv.8, if your Bench ¡s full, or you don't have your key pieces, Buy Exp to level up to Lv.9. If you don't have the mentioned concerns, refresh your Store with Interest for God of Thunder. Once you have it, keep levelling up and meanwhile deploying more pieces that provide control effects or AOE Damage.